> I’m trying to create a shadow file. But it doesn’t work.

>

> I have executed this command:

> create shadow 1 '/srv/firebird/master.shd';

> 

> The file is created in file system. But the file size is zero.

 Shadow is created and all pages from main database file is written to it. But shadow file

contents is not flushed by the Firebird and file system cached file metadata (such as file

size). It will be update a bit later, at last when file is closed.

> There is no entry in the table RDB$FILES.

  In "Autocommit DDL = ON" mode isql run DDL statements in separate transaction and

commits it automatically. But it doesn't commit "main" transaction where you run SELECT

statement. This transaction started before you created shadow and can't see changes

in RDB$FILES. Commit and run SELECT again.